Multiple wall paper bag



H Feb. 11,1941. K Y HAL 2,230,998

MULTIPLE WALL PAPER BAG Filed Nov. 16, 1 938- 2 Sheets-Sheet 1 F7616 Q I [NVENTOES HAROLD M MNDJETH- Z/GE COAKLEY- 7 (3 M 02M 11M 42" ATTONEYJ Feb. 11, 1941. CQAKLEY ETAL 2,230,998

MULTIPLE WALL PAPER BAG Filed Nov. 16, 1958 2 Sheets-Sheet 2 F769 I yO MFa- LIWM 14AM AT TOEINE r;

Patented Feb. 11, 1941 nu s!) STATES PATENT OFFICE 2,230,998 MULTIPLE WALL PAPER BAG poration of Missouri Application November 16, 1938, Serial No. 240,628

8 Claims.

This invention relates to new and useful improvements in multiply paper bags, and more particularly to such bags adapted to be used in the packaging of hydroscopic materials such, for

example, as sugar.

In the packaging of sugar and other similar products, it is important that the walls of the container in which the sugar is packaged, are so constructed that moisture cannot penetrate 10' therethrough and contact the sugar, as moisture has a tendency to cause portions of the sugar to harden and become lumpy, in which form it may adhere to the walls of the bag.

In the past it has been customary to package sugar in small containers such as cloth bags, the open tops of which are usually closed by sawing. Packaging sugar in cloth bags is more or less expensive, and attempts have therefore been made to package bulk sugar in small paper containers or bags. Conventional paper bags having single ply walls, have not proven very satisfactory for packaging sugar and other such products, because of the porosity of the walls of the bag permitting moisture to penetrate. Bags having multi-ply'walls have also been used, but these have similarly presented a problem in that the moisture in the paste used for sealing the bag mouth walls would frequently penetrate the inner plies of said walls, and thus contact the sugar and cause portions of it to become lumpy and adhere to the inner surface of the bag walls.

After considerable experimental work in an attempt to overcome this difiiculty, we discovered that the moisture in the paste may be prevented 35 from penetrating the inner plies of the bag top walls, if portions of the inner surfaces of the plies of the bag walls are suitably waterproofed, whereby the moisture in the paste cannot penetrate the inner plies of the bag walls.

The water proofing utilized for this purpose may be in the form of a thin sheet of rubberized material, such as latex, which is interposed between the plies of the bag top walls, or it may be applied in the form of a liquid to form a coating ed, the water proof material is so applied to the thereon. When the bag top walls are thus treatwater proof material or agent will be interposed between the contents of the bag body and the paste used in the operation of securing the walls forming the bottom of the bag, and also between the plies of the edge portions of the blank which are overlapped and secured by gumming to form the longitudinal seam of the bag body. If the bag body and bottom have been completed sometime prior to filling the bag, so that the paste used in securing these wall portions in place has thoroughly dried, then it is not necessary to thus water proof the bottom wall portions of the bag, nor the overlapped wall portions forming the seam of the bag body.

It is, therefore, an object of the present invention to provide a bag having certain portions of its walls treated with a suitable water proof agent whereby moisture in the paste used for closing the ends of the bag, cannot penetrate through the inner plies of the bag walls and contact the sugar or product contained in the bag.

Other objects of' the invention reside in the unique manner of applying the Water proof agent to one or more of the walls of the bag mouth, whereby when the 'bag top walls are folded into closing and sealing relation and suitably united by pasting, the water proof agent will be inter posed between the contents of the bag and the paste applied to the bag mouth walls; in the construction of the bag bottom whereby portions of the walls thereof are similarly treated to prevent moisture in the paste from penetrating the inner plies of the bag walls; and in the application of a suitable water-proof agent between the plies of the edge portions of the blank which form the longitudinal seam of the bag body, whereby the bag may be completed on a suitable bag making machine, filled, and its top closed, all in one cycle of operation, without danger of the moisture in the paste used in the construction of the bag bottom and the longitudinal seam of the bag body penetrating the inner plies of the bag walls and damaging the sugar.

Other objects of the invention will appear from the following description and accompanying drawings and will be pointed out in the annexed claims.

In the accompanying drawings, there has been disclosed a structure designed to carry out the various objects of the invention, but it is to be understood that the invention is not confined to the exact features shown as various changes may be made within the scope of the claims which follow.

Figure3 is a perspective view of a filled bag with one of 'the bag mouth walls folded inwardly over the material;

Figure 4 is a top view of a sealed bag showing in dotted lines the location of the water proof agent;

Figure 5 is a detail sectional view on the line 5-5 of Figure 4 on a larger scale, showing the water proof material interposed between the paste and the contents of the ba Figure 6 is a view showing the top of an empty bag with the water proof agent applied thereto in a slightly difierent manner;

Figure 7 is a side view of a bag showing the bottom partially completed;

Figure 8 is a side view of the lower portion of the bag tube;

Figure 9 is an enlarged detail sectional view on the line 9-9 of Figure 8; showing the manner of applying the water proof material between the plies of the bag walls adjacent the bottom of the tube;

Figure 10 is a view showing the bottom of the bag completed; and

Figure 11 is a detail sectional view on the line ll--ll of Figure 7, showing the water proof material applied between the plies of the edge portions of the blank from which the tube is made whereby the seam in the bag is rendered water proof.

In the selected embodiment of the invention herein disclosed, there is illustrated for purpose of disclosure, a bag of the flat type generally indicated by the numeral 2 and having a satchel bottom 3. The invention is more particularly applicable to bags having multi-ply walls, and in the present instance the walls of the bag are shown comprising an outer ply 4 and an inner ply 5. These plies, as is well known, are usually secured together at the upper and lower portions of the tube from which the bag is made, by suitable gumming to prevent displacement of the plies.

In the packaging of certain commercial products such, for example, as sugar, which is of a hydroscopic nature, and has an afiinity for moisture, it is essential that means be provided for preventing the moisture in the paste used in closing the bag top walls from penetrating the inner plies of the bag walls and contacting the sugar. When the sugar is packaged in paper bags, as contemplated in the present invention, the moisture in the paste used in securing the walls of the bag mouth in closing and sealing relation, may penetrate the inner plies of the bag walls because of the porosity of the paper, whereby the moisture contacts the sugar and causes it to become lumpy adjacent the bag top walls. The moistened sugar also adheres to the inner surfaces of the bag top walls and hardens or crystallizes thereon, which is very undesirable in that it is not welcomed by the trade and obviously may bag top walls to secure them in position cannot penetrate the inner plies of the bag walls.

In Figures 1 and 2 we have shown the water proof material, generally indicated by the numeral 6, as being applied between the plies of the end wall 1 of the bag top, which wall is first folded inwardly over the contents of the bag in the operation of closing the bag mouth with the type of closure shown in Figure 4. The water proof material may be applied in various manners, as for example, -it may be applied in the form of a liquid to one or both, plies of certain portions of the bag walls in the construction of the bag tube, or it may be applied in the form of a thin sheet. We have found latex to be a very desirable material for water-proofing the bag walls, as it may be applied to the surfaces thereof in liquid form, whereby it seals the pores of the paper and renders the treated wall portions absolutely water proof. The area covered by the water proofing 6 preferably extends slightly beyond the full width of the end wall I, as shown in Figures 2 and 3, and downwardly from the top edge of the end wall I to a point whereby when the end wall I is folded inwardly over the contents of the bag, as shown in Figure 3, and paste is applied thereto as shown at 8, the water proofed area 6 of the end wall I will be disposed between the paste-covered area 8 and the contents of the bag, whereby it is impossible for the moisture in the paste 8 to penetrate the inner ply 5 of the end wall I.

By reference to Figures 3 and 5, it will be noted that when the bag mouth walls are folded into sealing relation, the water proofed area 8 will be disposed between the contents of the bag and the paste applied between the bag top walls to secure them in closed relation. Thus by the application of the water proofing 6 between the plies of the end wall I, the moisture in the paste cannotpenetrate the inner ply 5 and contact the contents of the bag.

In Figure 6 there is shown an upper portion of an empty bag wherein the waterproofing is applied in a slightly different manner. As here shown, the water proofing is applied between the plies of all of the bag mouth walls in a plurality of areas indicated by the numerals 9, II and I2, separated by blank spaces l3. The blank spaces i3 are located at the fold lines of the bag top walls, whereby the water proofing will not interfere with the folding of the bag top walls into closing and sealing relation. The locations of th blank spaces It are dependent upon the particular manner in which the bag top walls are folded into closing and sealing relation.

In some instances it may be found desirable to construct and fill the bags in one cycle of operation, as for example, in one machine or perhaps two machines arranged in close proximity. In such cases, the paste used to unite together the wall portions forming the bottom of the bag and also the marginal edges I4 and I5 of the blank, which form the seam I6 of the bag body, may still be wet" or "moist" when the sugar is delivered into the-bag. As long as the paste is wet, the inner surfaces of the inner piles of the seam l6 and bottom wall of the bag body may also be wet or moist, because of the penetration therethrough of moisture in the paste, which would cause the sugar to become lumpy along these surfaces.

To overcome this difilculty when filling freshly made bags, we propose to suitably water proof the freshly pasted portions of the bag walls whereby the moisture in the wet paste cannot penetrate the inner plies of the walls of the bag body. To thus water proof the seam l6 and bottom of the bag body, we propose to apply a strip of water proofing, generally indicated by the numeral l1, between the plies of the walls of the lower end of the tube, as best illustrated in Figures 8 and 9. This strip of water proofing may extend around the entire circumference of the bag tube, or only certain areas thereof may be water proofed whereby a plurality of water proof areas ii are provided which are spaced apart as shown at IS in Figures 8 and 9. The water proofed areas I! are so applied between the plies of the bag walls, that when the wall portions of the lower end of the tube are folded into closing and sealing relation as shown in Figures 7 and 10, the water proofing will be disposed between the contents of the bag body and the paste applied between the walls forming the bag bottom, as will be readily understood by referenceto Figures 7 and 10.

In the formation of a satchel bottom, the lower edge of the tube is slitted, as best shown at l9 and 2| in Figure 8, thereby providing side flaps 22 and 23 adapted to be folded inwardly over the wall portions 24 and 25 of the tube along fold lines 26 and 21, to complete the formation of the bag bottom, as shown in Figure 10. The paste may be applied to the wall portions 24 as indicated at 28 in Figure 7 and to the outer surface of the flap 22, whereby when the walls forming the bottom of the bag are folded into closing and sealing relation, as shown inFigure 10, the water proof material will be interposed between the pasted areas of the bag bottom walls and the contents of the bag so that moisture in the paste cannot penetrate the inner ply of the bag bottom and contact the sugar as hereinbefore stated.

The seam iii of the tube is similarly treated by applying water proof material .32 betwen the plies ofone edge of the blank from which the tube is made, whereby when the edges of the blank are secured together as shown in Figure 11, the water proof material will be interposed between the pasted areas of the seam and the contents of the bag, thereby preventing the moisture in the paste from penetrating the inner ply. The paste is preferably applied between the plies of the walls at the points indicated at 33 and 34, it being unnecessary for all practical purposes to apply paste at the point 35 'between the inner plies of the bag tube. Paste may also be applied at the point 35, if desired.

In the drawings, we have shown the invention applied to a bag of the usual flat type having a satchel bottom and in which the bag top walls are folded into closing and sealing relation, as shown in Figure 4, commonly known to the trade as the Deltaseal. It is to be understood, however, that the invention may be embodied in various other types of bags and closures, where applicable, without departing from the scope of the invention. It is alsoto be understood that we do not wish to be limited to any particular material for water proofing the areas between the plies of the bag walls asthe invention in its broadest aspect is directed broadly to the application of any suitable water proof material at the points specified, whereby the water proof material will always be interposed between the freshly pasted areas or surfaces of the bag walls and the contents of the bag body, so that moisture in the wet paste cannot penetrate the inner piles of the bag walls and contact the sugar or other product contained in the bag.

We claim as our invention:

1. A bag made from a tube of multi-ply material, the wall portions of one end of said tube being folded into closing and sealing relation to form the bottom of the bag, and asuitable moisture proof agent interposed only between the plies of the wall portions at the top of the bag and so disposed that when the bag top walls are folded into closing and sealing relation the water proof agent will be interposed between the contents of the bag body and the paste applied to the top wall portions to unite said walls together, said water proof agent preventing moisture in the paste from penetrating the inner piles of the bag top.

2. A bag made from a tube having multi-ply walls, one end of said tube being closed to form the bottom of the bag, a suitable water proof agent interposed only between the plies of the bag top wall which is initially folded inwardly over the contents of the bag in the operation of closing the bag mouth, and whereby said water proof agent will be interposed between the con tents of the bag body and the paste applied to the bag top walls to unite them together, thereby preventing moisture in the paste from penetrating the inner ply of the bag top walls and contacting the contents of the bag.

3. A bag made from a tube having multi-ply walls, one end of said tube being closed to form a rectangular bottom for the bag and whereby the bag body will comprise end and side walls, a suitable water proof agent interposed only between the plies of the upper portion of the end wall which is initially folded inwardly over the contents of the bag in the operation of closing the bag mouth, and whereby said water proof agent will be interposed between the contents of the bag body and the paste applied to the bag top walls to unite them together, whereby moisture in the paste cannot penetrate the inner ply of the said initially folded end wall and contact the contents of the bag.

4. A bag made from a tube having multi-ply walls, one end of said tube being closed to form a rectangular bottom for the bag and whereby the bag body will comprise end and side walls, a suitable water proof agent interposed only between the plies of the upper portion of the end wall which is initially folded inwardly over the contents of the bag in the operation of closing the bag mouth, said water proof agent extending downwardly from the upper edge of said end wall and its lateral dimension being substantially equal to the width of said end walls, thereby the water proof agent will be interposed between the contents of the bag body and the paste applied to the bag top walls to unite them together, whereby moisture in the paste cannot penetrate the inner ply of said initially folded end wall and contact the contents of the bag.

5. A bag made from a blank of multi-ply material having opposed edges overlapped and united by a suitable paste to form a seam and whereby a tube is provided, the end wall portions of said tube being folded into closing and sealing relation to form the bottom and closed top of a filled bag, respectively, and a suitable moisture proof agent being inserted only between the plies of said folded end walls and said seam thereby preventing the moisture in the paste from penetrating the inner piles of the closed bag ends and said seam and contacting the contents of the bag.

6. A bag made from a tube of multi-ply material, one end of said tube being closed to provide the bottom of the bag, a suitable water proof agent applied only between the plies of the end wall of the bag top which is initially folded inwardly over the contents of the bag body, in the operation of closing and sealing the/bag mouth, and whereby when the oppositely disposed end wall and side walls of the bag mouth are folded inwardly over said initially folded wall, the water proof agent will be interposed between the contents of the bag and the paste applied to the bag mouth walls to secure them together, thereby preventing moisture in the paste from penetrat- 'ing the inner plies of the walls of the bag top and contacting the contents of the bag.

7. A bag made from a tube having multi-ply walls, one end of said tube being closed to form the bottom of the bag, a coating of latex applied only to the inner surface of one of the plies of the bag top wall which is initially folded inwardly over the contents of the bag in the operation of closing the bag mouth, and whereby said coating of latex will be interposed between the contents of the bag body and the paste applied to the bag top walls'to unite them together, thereby to prevent moisture in the paste from penetrating the inner ply of the bag top walls.

8. A bag made from a tube having multi-ply walls, one end of said tube being closed to form a rectangular bottom for the bag and whereby the bag body will comprise end and side walls, latex interposed only between the plies of the upper portion of the end wall which is initially folded inwardly over the contents of the bag in the operation of closing the bag mouth, said latex extending downwardly from the upper edge of said end wall and its lateral dimension being at least equal to the width of said end wall, whereby said latex will be interposed between the contents of the bag body and the paste applied to the bag top walls to unite them together, thereby to prevent moisture in the paste from penetrating the inner ply of said initially folded end wall.

LIGE COAKLEY. HAROLD V. KINDSETH. 

